Named driver's caution delivered verbally, being required (6,3)
I believe the answer is:
called for
'required' is the definition.
(calling for is a kind of requiring)
'named driver's caution delivered verbally' is the wordplay.
'named' becomes 'called' ('call' can be a synonym of 'name').
'driver's caution' becomes 'fore' (warning shouted by golfers - golfers 'drive' balls).
'delivered verbally' indicates a 'sounds like' (homophone) clue.
'fore' is a homophone of 'for'.
'called'+'for'='CALLED FOR'
'being' is the link.
(Other definitions for called for that I've seen before include "summoned" , "Justified" .)